Joel tiffany



gleiten grains guten-t` @ffice JOEL' TiFFANY, or ALBA NY, NEW YORK.

` Letta-8 Patent N0'. 73,138, dated January 7, 1868.

IMPROVED APPARATUS POR PREPARING PAPER-STOCK.

itin Stlgrhnlt nient tu in ilgtse trttrrs gntrnt filmmaking pnt at tigesame.

TO ALL WHOM IT MAY CONCERN:

Be it known that I, JOEL TIFFANY, of the city andcounty of Albany, andState of New York, have invented a new and improved Process for TreatingPaper-Stock for the Manufacture of Paper; and I do hereby declare thatthe following is a full and exact description thereof, reference beinghad to the accompanying drawings, 'and to the letters marked thereon. f

The nature of my improvement consists in the manner-of preparing mystock before putting the same into the reducing-vessel, the manner ofpreparing my reducing-liquor, tlieinanncr of bringing the stock andreducing-liquor together, and the means by which I apply my process. l

First. The stock should be prepared by being cut, crushed, ground, orbroken into small'fragments, for the purpose of exposing alarge surfaceto the action of the reducing-liquor, and for the greater facility ofpacking the same in the reducing-vessel. The stock thus prepared may besoaked or steamed so as to soften the parts of the stock, and also toadmit of being more closely packed in the` reducing-vessel. But if thestock has been thus soaked or steamed, before putting the saine into thereducing-vessel, the water should, as far ,as possible, be removed fromthe pores and cells ofthe same by pressing, or the air should beexhausted from the reducingvessel after 4the stockA has been placedtherein. The reason is obvious. The presence of water in the cells ofthe stock excludes the free access ofthe lalkaline or caustic liquorsthereto, and ultimately reduces the strength of the caustic liquor bythe per cent. of water present in the stoclc' at the time of itsintroduction thereto. If the stock is to be soaked prior to theintroduction ofthe reducing-liquor thereto, it should be soaked in acaustic liquor of the same-character as that with which it is to besubsequently treated. But the presence even of the caustic liquor in thecells of the stock acts-unfavorably upon the action of thereducing-liquor, when introduced according to my improved process, byreducingr `the temperature of the liquor, and consequently aifccting itsaction upon the stock. For these reasons previous soaking andsteaming-of the stock before the introduction of thc boiling liquor are notdeemed to be an essential part of this process. The vacuum-process,consisting in exhausting the airA from the reducing-vessel `after thesame has been charged with stock, and preparatory to the introduction ofthe reducing-liquor to the stock, may be resorted to with advantage whenthe conveniences exist for applyingV it. So likewise may thepneumatic-process, consisting in the forcing into v the reducing-vesselatmospheric air to create a pressure upon the liquor and stock, to forcethe liquor into all f the pores and cells of the stock, whereconveniences to apply the same exist. But neither the vacuum norpneumatic-process is so essential in connection with this process `aswith others-where the reducing-liquor is heated while it is in contactwith the stock. i i

Second. The stock, having been prepared by preliminary cuttings,bruisings, Ste., is packed into the reducing-vessel, as compactly as isdesired, by any of the ordinary means of doing the same, after which thereducing-vessel is closed steam-tight, and is connected, by means ofstrong pipes having stop-cocks in them, with the vessel containing thereducingdiquor, as hereinafter described. i

The reducing-liquor is prepared in the usual manner of preparing causticliquors for treating paper-stock, and of a degree of causticityproportioned to the refractory character of the stock to be treated. Forthe Hag, grape, straw, hemp, flax, and similar Afibrous substances, astrength o f causticity varying from 12 to 2 Baume is sufficient.Foru'cod and other more refractory stocksra strength varying from`3 to15 Baume muy benecessary. The \caustic liquor, when thus prepared, ischarged into a vessel capable of being closed steamtight, and ofsustaining an internal pressure 0f from two hundred to tive hundredpounds to the square inch, and it is to be there heated to a temperatureconsiderably higher Ithan the highest temperature desired to be used inthe reducing-sessel. As soon as the desired temperature is obtained inthe heatingvessel, the stock having been properly packed into thereducing-vessel, and the same having been closed steam-tight, thelreducing-liquor is th`e1rintroduced into the reducing-vessel, and uponand into the stock, by mea-ns' of turping the stop-cock in the pipeconnecting the two vessels. The ci'ect-of bringing the liquor and thestock together in the reducing-vessel, in this highly-heated state ofthe liquor, is to produce an instantaneous action upon all parts of thestock, and the greatest intensity of action on-its first introduction tothe stock, so that the mode of applying the liquor to the stock isbythis process the reverse of all other processes, thus cbviating diihcul=tics to which all others are subject. Thus, by the ordinary process ofheating the liquors after they have been brought into contact with thestock, causing a progressive action of the liquorupon the stock by thegradual increase o f heat and pressure, until the highest heat andpressure, and consequently the greatest intensity of action, isattained, certain unfavorable results inevitably follow. That portion ofthe stock iirst acted upon and reduced to apulpy condition, while theheat and pressure are increasing, to reach the' more interior andrefractory portions of the stock, continues subject to the intenseaction ofthe reducinglliquor until the whole body of the stock isreduced. Consequently, that portion ofthe stock is over-treated, and ina great measure destroyed, causing an increased expenditure of alkali,of time, a waste ot' the stock, and an injurious effect upon the char-Yacter of the bre. To obviate these dthculties, many expedicnts have beenresorted to with some effect. The

introduction of oleaginous substances to protect the external portionsofthe stock from the action ofthe caustic liquor, until the necessaryamount of heat and pressure should be produced to reach into all thecells and pores -of the stock, produced a favorable result. So,likewise, the resort to the vacuum and pneumatic-processes for thepurpose of introducing the caustic liquor to all parts ot' the stockbeforeY the boiling-process should begin, was found beneficial, astending to produce the result obtained by my improved process. But allthese were more or less expensive, and imperfect in their operations andeli'ects. By my process,`I at once obtain the benefit of all necessaryheat and pressure to carry the caustic liquor into every pore and cellof the stoel; when they are rst brought together in the reducing-vessel,so that the greatest. intensity of action takes place at the time whenthe greatest intensity of action is required, and it acts simultaneouslyand uniformly upon every `part of the stock, and consequently produces aspeedy and uniform result, effecting avery great saving of time,

chemicals, stock, and producing a very superior quality of pulp. f

After the stock and liquor are thus brought together, no more heating ofthe liquor and stock will be lrequired. After standing and soaking fromthirty minutes to two hours, according to the character of the stock,the liquor and stock should be blown off into a washing-tub, with whicheach reducing-vessel is connected by a large, strong pipe, coming outnear the bottoni of each reducing-vessel, and closed by means of a largefaucet, or other suitable means.

To illustrate the means by which my process is applied, or may beapplied, I herewith subjoin the following figures or drawings, which aremade a part of my specification Figure 1 is a representation oftheseveral vessels used in my process, ina convenient and proper relationto each other, with their respective connections indicated. Thus G Grepresent two i'educingvessels, to be used alternately; A A representthe man-holes, or places for charging them` with the stock to betreated; B represents the vessel in which the reducing-liquor is to beheated preparatory to its introduction to the stcckl; S S, the pipesconnecting such vessel with the reducing-vessels G G; C C represent twopans in which the reducingliquors are mixed, and thestrength thereofadjusted to the character of the stock to be' treated; and gg representthe tubes connecting the pans with the heating-vessel B; 'D representsthe washing-tub, into which thc stock is to he discharged through thepipes or tubes R R; a a a a, 36o., represent a chamber surrounding thcheating-vessel B, and partially surrounding the reducing-vessels G G,and constitute a part ofthe fire-chamber ofthe furnace E, connecting thefurnace with the escape-fines therefrom, and are designed as a means ofaiding to heat the liquor inthe vessel B, andto keep hot the liquorafter it is discharged into the vessels G Gr. But in practice, so muchof the dues a a a. as partially surround the reducing-vessels G G, mustbe closed, so as to exclude the fire therefrom until after the vesselsare filled or charged with the reducing-liquor, to avoid burning thestock therein. In any suitable place above these reducing-vessels may besituated the bin H, for containing the prepared stock to be charged intothe reducing-vessels G G.

.Figure 2 represents a front view of thc heating-vessel B, over thefurnace E, surrounded by the tire-chamber a a a a, tc., with a partialview of the reducing-vcsscls G G, and the pipes S S, connecting theheating-vessel VB with the reducing-vessels G G und their stopsy at t t.

Figure 3 represents the reducing-vesselsG G, with their connection withthe washing-tub D bymeaus of pipes R R and stops y y. It also.shows theman-holes A A. Y

Having thus described rny said improvement, I will proceed to set forthmy claim.

1. I claim the use of a strong, close vessel for heating the entireliquor to be usd in the reducngvessel to its maximum heat beforeintroducing the same into the reducing-vessel, in combination with thereducing-vessel, substantially in the manner and for the purpose abovedescribed.

2. I claim the use of a close vessel, B, in combin ation with areducing-vessel, G, to be used-with their several connecting-pipes,substantially in the manner and for the purpose above described.

I JOEL TIFFANY.

Witnesses:

EDWARD WADE, CHARLES B. Kino.

